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combination with lime as phosphate of lime, to the extent of O10 to 

 1*25 per cent, (or lOOlbs. of this burned lime contains 2^1bs. of 

 phosphate of lime). 



Marls consist of carbonate of lime, generally resulting from 

 the fragments of shells which have accumulated at the bottom of 

 fresh water lakes, which have generally been filled up by clay or 

 sand, or by the growth of peat. They contain from 1 to 2 per cent, 

 of phosphate of lime, and at times small amounts of potash. 



Marling only pays where the material is close at hand and can 

 be put on the land at a cost of a few shillings a ton. An application 

 of two to three tons to the acre is by no means excessive. 



Gypsum, or hydrated calcium sulphate, has been much used as 

 a manure,' but as it occurs in superphosphate and is not charged 

 for, is rarely applied to crops nowadays. It occurs in places 

 crystallised, and is found very useful for leguminous plants, 

 especially for red clover, lucerne, etc. Applied from two to six 

 cwts. per acre. Supplies lime and sulphate to the crops and acts as 

 a solvent, which sets potash free from its state of dormant 

 combination in the soil. Appears to promote the process of nitri- 

 fication. Is a valuable absorbent on the manure heap and in 

 stables, cow sheds, and poultry yards, where it fixes the volatile 

 ammonia into non-volatile sulphate of ammonia. Very useful in 

 reclaiming alkaline salt patches containing carbonate of soda. 



Ashes. Supply in small quantities magnesium, potassium, 

 calcium, iron, phosphorus and sulphur all mineral matters neces- 

 sary to the growth of plants, and for that reason they constitute a 

 very good fertiliser. Besides their value as plant food, they also 

 have on it a mechanical effect similar to that of lime. They are 

 especially useful on light and sandy lands, rendering them moister. 

 The value of ashes vary with the kind of wood burned, and with the 

 care that has been taken of them. Limekiln ashes can at times be 

 obtained at a reasonable price. They contain about 1 per cent, of 

 potash and phosphoric acid and about 40 per cent. lime. 



Green Manuring affords one of the best and cheapest methods 

 of adding humus or organic mould to poor sandy soils more 

 especially. The term is applied to some quick-growing crop which 

 is ploughed in green. Two classes of plants are used : those which 

 are not exacting in their demand for plant food and constitute a cover 

 in the winter which checks loss by washing or drainage, and those 

 which gather plant food from the air as well as from the subsoil and 

 leave it on the surface for the use of succeeding crops. To the first 

 class belong rye, buckwheat, rape, dandelion (Cape weed), Cape and 

 beardless barley ; to the second, the legumes clovers, peas, vetches, 

 lupins. By the process of green manuring, loose soils are made more 

 retentive, and clay soils lighter. Cow peas, although very desirable as 

 green manure, are not used in orchards where winter-growing 

 plants are exclusively grown. For that purpose the most desirable 

 plants are crimson clover (Trifolium incarnatum}, an annual which 

 germinates and develops quickly. Eight to ten pounds of seeds w ill 



